Problem: $ { \left[\begin{array}{r}{-1} \\ {0} \\ {-1}\end{array}\right]+\left[\begin{array}{r}{3} \\ {-2} \\ {0}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{r}{-1}+{3} \\ {0}+{-2} \\ {-1}+{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{r}{2} \\ {-2} \\ {-1}\end{array}\right]}$